1. Field of the Invention
The present invention relates to a safety electrical receptacle for installation into a standard electrical outlet box, in particular, a safety electrical receptacle utilizing a magnetic switch.
2. Description of the Related Art
Child safety is an ever-present concern to families and the public at large. Electrical outlets in the home as well as any environment to which children and any adult who may be mentally impaired are likely to encounter present a serious danger. Items that are electrically conductive, such as pins, scissors, needles or other pointed objects, have been inserted into `live` electrical wall outlets causing serious if not fatal electrocution. This danger from electrocution is especially great in countries or in places where 220 volts is being used. In other instances, in both commercial and industrial settings, improper maintenance or care of electrical outlets have caused electrocution.
In response to this problem, numerous attempts have been made to prevent such occurrences. Devices have been made to obstruct the electrical connection ports so that foreign objects cannot be inserted. However, in order to make the outlet receptacle useful, such devices must be reasonably easy to remove or the outlet receptacle cannot be used. Therefore, the safety provided by this type of device is limited to very young children or others who cannot remove the device from the outlet connection port.
However, either through repeated use or time, the devices either fail to operate properly or can be easily removed by hand and, therefore, are not absolutely "childproof" even for very young children or substantially impaired adults.
Other more complex attempts have been made to deactivate the outlet receptacle if it is not being properly used. Many of these devices use various configurations of a magnetic switch in order to deactivate the outlet receptacle.
U.S. Pat. No. 4,242,657, issued to Chaillot on Dec. 30, 1980, discloses two matched pairs of a magnet and a ferro-magnetic material member that is attracted by a magnet but retains little magnetism once the magnet is removed such a soft iron. One pair is used to bias the device in an inactive state so that the electrical connection ports are not alive. A second pair having a magnet substantially stronger than the magnet in the first pair is used to activate the outlet receptacle when a plug is inserted therein. The permanent magnet is attached to the plug and the attractable material is attached to outlet receptacle. This arrangement is expensive to produce and requires that the magnets be precisely calibrated in order for the device to function.
U.S. Pat. No. 4,317,969, issued to Riegler et al. On Mar. 2, 1982, discloses an electrical line connector. This design also features two magnets. A biasing spring is used to hold the distributor part in an inactive state. A permanent magnet affixed to the collector port attracts a holding magnet which causes the distributor part to become active. A contact plate is disposed between the two magnets. This device is also expensive to produce and cannot be used as a replacement for standard outlet receptacles and standard plugs.
Still another variation is disclosed by Kersman in U.S. Pat. No. 3,868,160, issued on Feb. 25, 1975. This design features a flexible member having a contact adjacent to each end with the flexible member being connected to a magnet or ferro-magnetic material nearer to one end of the flexible member than to the other end. The flexible member is biased so that it is bent such that the two contacts do not activate the outlet receptacle. A corresponding permanent magnet in the plug causes the flexible member to activate the outlet receptacle once the plug is inserted into the outlet receptacle. The device is dependent on the critically adjusting the ease of flexing the flexible member in comparison with the magnetic force provided by the magnet.
The above described devices do not meet the requirement of a simple to build, magnetically operated switch within a plug/outlet receptacle that can be used within any standard sized outlet box or with any electrical system configuration.